Charging Collection Function (CCF) is a transactional entity that implements offline charging in a telecommunications network. Offline charging is accomplished via network elements with integrated Charging Trigger Function (CTF), reporting session and network usage to the CCF via Diameter Accounting Requests (ACRs), which are acknowledged by the CCF with a Diameter Accounting Answer (ACA) for each ACR.
For simple voice calls, the count of ACRs for a session is typically 3 to 10, depending on the number of CTFs reporting the session. However, with Long-Term Evolution (LTE) and support of flow-based bearer charging, the ACR count may increase to 30 or more per session. The session duration itself may increase to ten minutes or longer, making it necessary for the CCF to hold session information in RAM for a longer duration.
An increase in accounting traffic puts a huge processing load on the CCF servers in a telecommunications network, particularly when Tier-1 service providers with sizeable subscriber populations are served. Higher traffic increases the need for processing resources. In addition, as the duration of sessions increases, CCFs must retain necessary information in memory for a longer period. Thus, the need for resources—both the need for central processing unit (CPU) cycles and the need for available RAM—may be elevated for a significant period of time each day.
To handle increased traffic, and the increased central processing unit (CPU)-intensive transactional processing, more powerful server architecture has been developed, such as multi-core processors and blade-based architectures. Existing systems use dual-core, quad-core, hex-core, and octa-core CPUs, for example. Some blade servers can host one or more multi-core CPUs, for example. Such equipment enables vendors to provide high package density in a small form factor, and increased computing power to handle the increased traffic.